Physics & Astrophysics colloquium is Friday Physics & Astrophysics will hold a colloquium at 4 p.m. Friday, Nov. 13 in 211 Witmer Hall. Jianglong Zhang, Atmospheric Sciences, will present. Coffee and Cookies are at 3:30 p.m. in 215 Witmer Hall. The impact of aerosols remains as one of the largest uncertainties in the current climate change and climate forcing studies. Aerosols, which are suspended particles in air, affect climate directly by reflecting and absorbing solar energy, thus perturbing the earth’s radiation balance, and indirectly by modifying cloud properties. Beside their critical roles in climate studies, aerosols are also known for their importance in a suite of scientific applications such as air quality and visibility forecasts. As a consequence, extensive studies have been conducted to study aerosol optical properties, aerosol and cloud interactions, and aerosol induced climate impact. In this presentation, we will discuss the role of aerosols in the current climate studies, mention the ongoing aerosol researches that involve ground-based, in situ, and space-borne observations, and show the applications of radiation (such as light scattering by non-spherical particles) in aerosol studies. I will also demonstrate recent achievements in modeling and forecasting of aerosol optical properties by applying 2-D and 3-D satellite observations into numerical models through aerosol data assimilation. -- Connie Cicha, Administrative Secretary, Physics & Astrophysics, connie_cicha@und.nodak.edu, 7017772911